This PR updates the Rust toolchain to recent nightly.
Most of the changes are related to fixing newly added warnings and adjusting the feature flags. Also the formatter changed its behavior slightly, causing some whitespace changes.
Other points:
* Changed debug level of the `buildscript` profile to `lint-tables-only` — this should improve the build times and space usage somewhat.
* Moved lint configuration to the worksppace `Cargo.toml` definition. Adjusted the formatter appropriately.
* Removed auto-generated IntelliJ run configurations, as they are not useful anymore.
* Added a few trivial stdlib nightly functions that were removed to our codebase.
* Bumped many dependencies but still not all:
* `clap` bump encountered https://github.com/clap-rs/clap/issues/5407 — for now the warnings were silenced by the lint config.
* `octocrab` — our forked diverged to far with the original, needs more refactoring.
* `derivative` — is unmaintained and has no updated version, despite introducing warnings in the generated code. There is no direct replacement.
Introduce new APIs for managing focus and using focus to inform delivery of keyboard events.
Use new APIs to implement the following behavior:
Focus:
- If the component browser is opened, its initial state is *focused*.
- If the node input area's text component is clicked, the component browser's state becomes *blurred*.
- If a click occurs anywhere in the component browser, the component browser's state becomes *focused*.
Event dispatch:
- When the component browser is in the *focused* state, it handles certain keyboard events (chiefly, arrow keys).
- If the component browser handles an event, the event is not received by other components.
- If an event occurs that the component browser doesn't handle, the node input area's text component receives the event.
[vokoscreenNG-2023-06-29_10-55-00.webm](https://github.com/enso-org/enso/assets/1047859/f1d9d07c-8c32-4482-ba32-15b6e4e20ae7)
# Important Notes
Changes to display object interface:
- **`display::Object` can now be derived.**
- Introduce display object *focus receiver* concept. Many components, when receiving focus, should actually be focused indirectly by focusing a descendant.
- For example, when the CB Panel receives focus, its descendant at `self.model().grid.model().grid` should be focused, because that's the underlying Grid View, which has its own event handlers. By allowing each level of the hierarchy to define a `focus_receiver`, focus can reach the right object without the CB panel having to know structural details of its descendants.
- When delegating to a field's `display::Object` implementation, the derived implementation uses the child's `focus_receiver`, which will normally be the correct behavior.
**Changes to `shortcut` API**:
- New `View::focused_shortcuts()` is a focus-aware alternative to `View::default_shortcuts()` (which should now only be used for global shortcuts, i.e. shortcuts that don't depend on whether the component is focused). It's based on the *Keyboard Event* API (see below), so events propagate up the focus hierarchy until a shortcut is executed and `stop_propagation()` is called; this allows sensible resolution of event targets when more than one component is capable of handling the same keypress.
Keypress dataflow overview:
DOM -> KeyboardManager -> FrpKeyboard -> KeyboardEvents -> Shortcut.
Low-level keyboard changes to support Focus:
- New `KeyboardManager`: Attaches DOM event handlers the same way as `MouseManager`.
- New *Keyboard Event* API: `on_event::<KeyDown>()`. Events propagate up the focus hierarchy. This API is used for low-level keyboard listeners such a `Text`, which may need complex logic to determine whether a key is handled (rather than having a closed set of bindings, which can be handled by `shortcut`).
- FRP keyboard: Now attaches to the `KeyboardManager` API. It now serves primarily to produce Keyboard Events (it still performs the role of making `KeyUp` events saner in a couple different ways). The FRP keyboard can also be used directly as a global keyboard, for such things as reacting to modifier state.
Misc:
- Updated the workspace `syn` to version 2. Crates still depending on legacy `syn` now do so through the workspace-level `syn_1` alias.
This PR changes build script's `ide watch` and `ide start` commands, so they don't use `electron-builder` to package. Instead, they invoke `electron` directly, significantly reducing time overhead.
`ide watch` will now start Electron process, while continuously rebuilding gui and the client in the background. Changes can be puilled by reloading within the electron, or closing the electron and letting it start once again. To stop, the script should be interrupted with `Ctrl+C`.
Implement generation of Java AST types from the Rust AST type definitions, with support for deserializing in Java syntax trees created in Rust.
### New Libraries
#### `enso-reflect`
Implements a `#[derive(Reflect)]` macro to enable runtime analysis of datatypes. Macro interface includes helper attributes; **the Rust types and the `reflect` attributes applied to them fully determine the Java types** ultimately produced (by `enso-metamodel`). This is the most important API, as it is used in the subject crates (`enso-parser`, and dependencies with types used in the AST). [Module docs](https://github.com/enso-org/enso/blob/wip/kw/parser/ast-transpiler/lib/rust/reflect/macros/src/lib.rs).
#### `enso-metamodel`
Provides data models for data models in Rust/Java/Meta (a highly-abstracted language-independent model--I have referred to it before as the "generic representation", but that was an overloaded term).
The high-level interface consists of operations on data models, and between them. For example, the only operations needed by [the binary that drives datatype transpilation](https://github.com/enso-org/enso/blob/wip/kw/parser/ast-transpiler/lib/rust/parser/generate-java/src/main.rs) are: `rust::to_meta`, `java::from_meta`, `java::transform::optional_to_null`, `java::to_syntax`.
The low-level interface consists of direct usage of the datatypes; this is used by [the module that implements some serialization overrides](https://github.com/enso-org/enso/blob/wip/kw/parser/ast-transpiler/lib/rust/parser/generate-java/src/serialization.rs) (so that the Java interface to `Code` references can produce `String`s on demand based on serialized offset/length pairs). The serialization override mechanism is based on customizing, not replacing, the generated deserialization methods, so as to be as robust as possible to changes in the Rust source or in the transpilation process.
### Important Notes
- Rust/Java serialization is exhaustively tested for structural compatibility. A function [`metamodel::meta::serialization::testcases`](https://github.com/enso-org/enso/blob/wip/kw/parser/ast-transpiler/lib/rust/metamodel/src/meta/serialization.rs) uses `reflect`-derived data to generate serialized representations of ASTs to use as test cases. Its should-accept cases cover every type a tree can contain; it also produces a representative set of should-reject cases. A Rust `#[test]` confirms that these cases are accepted/rejected as expected, and generated Java tests (see Binaries below) check the generated Java deserialization code against the same test cases.
- Deserializing `Code` is untested. The mechanism is in place (in Rust, we serialize only the offset/length of the `Cow`; in Java, during deserialization we obtain a context object holding a buffer for all string data; the accessor generated in Java uses the buffer and the offset/length to return `String`s), but it will be easier to test once we have implemented actually parsing something and instantiating the `Cow`s with source code.
- `#[tagged_enum]` [now supports](https://github.com/enso-org/enso/blob/wip/kw/parser/ast-transpiler/lib/rust/shapely/macros/src/tagged_enum.rs#L36-L51) control over what is done with container-level attributes; they can be applied to the container and variants (default), only to the container, or only to variants.
- Generation of `sealed` classes is supported, but currently disabled by `TARGET_VERSION` in `metamodel::java::syntax` so that tests don't require Java 15 to run. (The same logic is run either way; there is a shallow difference in output.)
### Binaries
The `enso-parser-generate-java` crate defines several binaries:
- `enso-parser-generate-java`: Performs the transpilation; after integration, this will be invoked by the build script.
- `java-tests`: Generates the Java code that tests format deserialization; after integration this command will be invoked by the build script, and its Java output compiled and run during testing.
- `graph-rust`/`graph-meta`/`graph-java`: Produce GraphViz representations of data models in different typesystems; these are for developing and understanding model transformations.
Until integration, a **script regenerates the Java and runs the format tests: `./tools/parser_generate_java.sh`**. The generated code can be browsed in `target/generated_java`.
